I am trying to use a Siemens S7-1200 PLC with Ignition for the first time. I have watched all of the videos on Inductive University and read many similar posts on the forum, but I can’t seem to get a tag to connect to the designer. Here are my tag settings.
I think I have the PLC set up correctly. I have allowed all access to the PLC. My only question is Do I have to add a DB to monitor the physical IO? I don’t see that referenced anywhere in any of the videos. Thank you in advance for your help.
Did you follow the instructions on this page?
Also consider using a flag area or a datablock for writing to the plc and start your tests with reading first.
I know writing to unused inputs was possible in very old legacy processors, but i don’t think it’s supported with a 1200. If IW144 is a real input module, writing to it is physically impossible.
Yes I followed that page. IW144 is a real input. It is a Thermocouple input. I also tried to change the tag to read only with no change. It will not show anything for the value of the tag. I’ve tried changing the OPC item path to a “M” value also. No difference. I will try adding a DB to the program to capture the value instead of trying to read directly from the PLC tags.
Reading the input should work, so there is a problem somewhere else.
Does the device show as connected on the gateway configuration page?
Just as a side note, flags are F instead of M.
That’s strange. Can you check the Rack and Slot number in the extended configuration. I have no cpu available right now, but i remember i had to change something there. You could try Slot 0 instead of the default.
I tested a S7-1200 connection with 8.0.8-rc1 and it worked without problems. The default settings Rack 0, Slot 1 are ok. The plc does not have a IW144 but the value is ok anyway.
I don’t know what changed from yesterday to today, but it works this morning. Maybe it was the power cycle I did when I left last night, I don’t know. Thank you all for you help with this.
Barring any bugs or interop issues that may pop up, it shouldn’t require any updates to Ignition. In theory if you updated your firmware and configured the server you should be able to connect to it now.
I’ve used the OPC-UA functionality in the S7-1500’s with great success in the past… I bet it will work fine for you on the S7-1200, especially if you don’t have to pull a very large volume of tags across.
